Apparatus and method for winding threads onto a former

ABSTRACT

An apparatus for winding a plurality of threads onto a former, wherein the apparatus has at least one ring traverse that at least partly surrounds the former. Via the ring traverse, threads are fed to the former from a plurality of different feed directions. With each feed direction there is associated at least one transfer element, from which the at least one thread is taken up on the former. The distance to the former axis is adjustable at least for some of the transfer elements.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The invention relates to an apparatus for winding a plurality of threadsonto a former. The invention further relates to a method for winding thethreads onto the former. The threads may include at least one fiberand/or two or more fibers which are fed and wound together.

2. Description of the Related Art

From practical experience it is already known how to wind fibers orfiber strands onto a former. The threads or fiber strands can beimpregnated beforehand with a resin, after which the impregnated fiberstrand is wound onto the former. The former is in particular acylindrical hollow body, such as a blow-molded plastic container. Theresulting end product can be used, for example, as a tank for liquids orgases or similar substances. In principle, it is also known frompractical experience how to feed at least one fiber to a former fromeach of a plurality of different feed directions. This feed of fibersfrom different directions is accomplished by what is known as a ringtraverse. The ring traverse is provided with a plurality of transferelements distributed around the former. During operation of theapparatus, at least one thread is taken up on the former from a transferelement. In the process, the thread can be brought up to the formertangentially, for example. The apparatuses known from practicalexperience have the disadvantage that the working technique that can beachieved therewith is poorly flexible and poorly variable.

SUMMARY OF THE INVENTION

In contrast, the technical problem underlying the invention is toprovide an apparatus of the type mentioned hereinabove, with which avery flexible and variable working technique with high functionalreliability and high precision in applying the starting turns ispossible. A further technical problem underlying the invention is toprovide a corresponding method.

To solve the technical problem, the invention includes an apparatus forwinding a plurality of threads onto a former,

-   -   wherein there is provided at least one ring traverse, which        surrounds the former at least partly, with which ring traverse        at least one thread can be fed to the former from each of a        plurality of different feed directions,    -   wherein at least one transfer element from which the at least        one thread is taken up on the former is associated with each        feed direction    -   and wherein the distance to the former axis or to the former can        be adjusted at least for some of the transfer elements.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention will be explained in more detail hereinafter on the basisof a drawing, which illustrates merely one practical example that is notintended to limit the claimed invention and in which, in schematicdiagrams:

FIG. 1 shows a perspective view of an inventive apparatus,

FIG. 2 shows a top view of an inventive ring traverse in a firstembodiment,

FIG. 3 shows the object according to FIG. 2 in a second embodiment,

FIG. 4 shows the object according to FIG. 2 in a third embodiment,

FIG. 5 shows the object according to FIG. 2 in a fourth embodiment,

FIG. 6 shows the object according to FIG. 2 in a fifth embodiment,

FIG. 7 shows an inventive ring traverse in a sixth embodiment, and

FIG. 8 shows a schematic diagram of an inventive distance adjustmentmeans.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

The term thread in the context of the invention means in particular atleast one fiber or two or more fibers. The at least one fiber,preferably two or more fibers, is taken up on the former from a transferelement. The fibers can be, for example, glass fibers, carbon fibers,aramide fibers or even plastic fibers.

In one embodiment, the former can be what is known as a liner, or inother words a former that remains in the product and becomes a part ofthe product. In other embodiments, the former can be a mandrel, which iswithdrawn from the product after a winding operation, and which isavailable once again for further winding operations. It is within thescope of the invention for a former to be driven in rotation during awinding operation.

The ring traverse is expediently provided with an opening for theformer. This means that the former axis passes through a central openingof the ring traverse. At least one thread or at least one fiber,preferably two or more fibers, is fed from each of several feeddirections with the ring traverse. For example, there can be eight feeddirections, and one or more fibers can be fed from each of these feeddirections. The number of feed directions may be less than eight (forexample 1, 2, 3, 4, 5, 6, 7) or greater than eight if necessary. Atransfer element is associated with each of these feed directions. It isat the transfer element that the fibers/threads being fed have theirlast contact with the ring traverse, after which they are taken up onthe former. Several configurations are possible for the transferelement. In the simplest case, the transfer element can be a deflectingpin, a deflecting rod or a roll or the like. According to a preferredembodiment of the invention, a transfer element is designed as a threadguide eye. This is a ring-shaped element with preferably circular crosssection. Other shapes such as open ring, square or polygonal may beused. The thread is fed to the former through the ring opening of thethread guide eye. Expediently, a thread guide eye is provided at the endof a transfer arm or transfer lever. Relative to the circumference ofthe former, the transfer elements are disposed around the former with adistance to the former.

It is within the scope of the invention for at least some of thetransfer elements to be disposed with equal distance to the former axis.According to a particularly preferred embodiment of the invention, alltransfer elements are disposed with the same distance to the formeraxis.

In a very preferred embodiment the distance to the former axis can beadjusted together or simultaneously or synchronously for at least someof the transfer elements. Preferably, the distance to the former axiscan be adjusted together, simultaneously or synchronously with a singleadjusting means (e.g., an adjuster). The approach movement of thetransfer elements relative to the former expediently takes placelinearly, especially radially or tangentially relative to the former.However, the approach movement of the transfer elements relative to theformer can also follow an arcuate path. Preferably, the distance to theformer axis can be adjusted together or simultaneously or synchronouslyfor all transfer elements of the ring traverse. In principle, however,it is also within the scope of the invention for the distances to theformer axis to be adjustable independently of one another for at leastsome or for all transfer elements.

According to a particularly preferred embodiment of the invention,transfer elements that are adjusted together or simultaneously orsynchronously are always disposed with the same distance to the formeraxis. The transfer elements are expediently disposed on a circle aroundthe former or around the former axis.

According to one embodiment of the invention, the thread guide of thetransfer elements has the shape of an arc or of a ring segment. Thethreads or the fibers then run over a curved guide surface of thetransfer element. According to another embodiment, a transfer element isdesigned as a thread guide eye. In this case the threads or fibers runthrough the opening of the thread guide eye, which has circular shape,for example.

According to one embodiment of the invention, the adjusting means and/oradjuster is designed with the criterion that the distance of thetransfer elements from the former axis be adjustable in the manner of aniris aperture. As an example, the adjustment of the distances of thetransfer elements can be achieved by operating with a closed-track camplate, to be explained in more detail in the description of the figures.

According to a very preferred embodiment of the invention, a suitablemotor, especially a servo motor or stepping motor, can be used for thedrive of the adjusting means. However, driving or actuation of theadjusting means for adjustment of the distance of the transfer elementscan also be accomplished pneumatically or servo-pneumatically orhydraulically or servo-hydraulically.

As an example, a crown gear in which toothed gears mesh or a bevel crowngear with associated bevel gears can be used for adjustment of thedistances of the transfer elements together. The adjustment of thedistances of the transfer elements can also be accomplished via a levermechanism. Furthermore, a plane spiral, for example, can also be usedfor adjustment of the distances of the transfer elements. The use ofpinions meshing with a toothed belt or with a cylindrical crown gear isalso possible for bringing about adjustment of the transfer-elementdistances. Moreover, the adjustment of the distances of the transferelements can also be achieved via a wedge-bar mechanism.

Also included in the invention is a method for winding a plurality offibers onto a former, wherein at least one thread is fed to the formerfrom each of a plurality of different feed directions by the transferelements associated with the feed directions, and wherein the distanceto the former axis is adjusted for at least some of the transferelements. According to a particularly preferred embodiment of theinventive method, the distance is adjusted simultaneously orsynchronously for at least some of the transfer elements and preferablyfor all transfer elements.

The invention permits a very flexible, variable and at the same timefunctionally reliable working technique via the inventive adjustment ofthe distances of the transfer elements. In particular, shorter movementpaths can be achieved during winding. Because of the flexible adjustmentof the distances, a high working speed and thus a high productivity canalways be achieved. Nevertheless, threads can be laid down moreprecisely than is possible in the arrangements known from the prior art.The products produced with the inventive method are thereforedistinguished by flawless quality. It can be further emphasized that theinventive apparatus is of less expensive and less complex constructionand therefore can also be made easily.

The figures relate to an apparatus for winding fibers 1 onto a former 2.In the practical example according to the figures, there is provided aring traverse 3 that completely surrounds former 2. In other words,former 2 or its former axis F passes through an opening 4 of ringtraverse 3. Via ring traverse 3, fibers 1 can be fed to former 2 from aplurality of different feed directions. Expediently two or more fibers 1can be fed from one feed direction. Associated with each feed directionis a transfer element 5, from which fibers 1 are taken up on former 2.In other words, the last contact of fibers 1 with ring traverse 3 takesplace at transfer element 5, before fibers 1 are taken up on former 2.According to the invention, the distance a to former 2 or to former axisF can be adjusted at least for some, preferably for all transferelements 5. FIGS. 2 to 7 show several adjustment options or severaladjustment means for this purpose. Preferably, the distance a of alltransfer elements 5 to former axis F is adjusted together orsynchronously. In principle, however, the distances of the individualtransfer elements 5 to former axis F could also be adjustedindependently of one another. Hereinabove and hereinafter, distance a ofa transfer element 5 means in particular the distance a from former axisF of the last point of contact of a fiber 1 on transfer element 5.

FIG. 2 illustrates a ring traverse 3 with three transfer elements 5. Inthis case, therefore, fibers 1 are fed to former 2 from three feeddirections. Transfer elements 5 in this case are designed as threadguide eyes 15, which are attached to transfer arms 16 functioning aslever elements. Each of these transfer arms 16 can be swiveled around aswivel shaft 6. Otherwise, each transfer arm 16 is provided with anoblong hole 7, in which a pin 8 fixed to a drive ring 9 engages. Duringrotation of drive ring 9, transfer arms 16 are swiveled in the directionof the two-headed arrows and in this way the distance a of thread guideeyes 15 to former axis F is varied. In this embodiment, distance a isadjusted simultaneously or synchronously for all transfer elements 5 orthread guide eyes 15 and all transfer elements 5 always have the samedistance a to former axis F.

The embodiment according to FIG. 3 operates with a bevel gear mechanismfor adjustment of distance a. In this case, a bevel gear 10 meshing witha bevel crown gear 11 is associated with each transfer element 5. Duringrotation of bevel crown gear 11, bevel gear 10 also rotates, as does thespindle 12 or screw attached to it. A nut 13 seated on the male threadof spindle 12 is displaced on spindle 12 when bevel gear 10 and spindle12 rotate. Thereby the distance of transfer element 5 from former axis Fis varied. In this case also, transfer elements 5 are designed as threadguide eyes 15, each of which is attached to a nut 13. In this embodimentalso, the distances a are varied simultaneously or synchronously for alltransfer elements 5 and all transfer elements 5 always have the samedistance a to former axis F.

The embodiment according to FIG. 4 also operates with a bevel gearmechanism. In this case also, a bevel gear 10 meshing with a bevel crowngear 11 is associated with each transfer element 5. During rotation ofbevel crown gear 11, each bevel gear 10 also rotates, and thereby anadjusting screw 14 engaging in bevel gear 10 is displaced. For thispurpose, the male thread of each adjusting screw 14 cooperates with afemale thread of associated bevel gear 10. To each adjusting screw 14there is attached a transfer element 5 designed as a thread guide eye15. In this case also, fibers 1 are fed to former 2 through the openingsof thread guide eyes 15. In this embodiment, the distances a of transferelements 5 or thread guide eyes 15 are adjusted simultaneously orsynchronously and all transfer elements 5 or thread guide eyes 15 alwayshave the same distance a to former axis F.

In FIG. 5 also, transfer elements 5 are designed as thread guide eyes15, each of which is attached to a transfer arm 16. During rotation of apinion 17 having eccentric disk 24, a cam acts on transfer arm 16, insuch a way that this can be displaced in the direction of the two-headedarrow. Pinions 17 are expediently driven via a circulating tractionmechanism, for example via a toothed belt 18 or via a chain. In thepractical example according to FIG. 5, toothed belt 18 is also guidedover deflecting pulleys, of which one deflecting pulley 19 expedientlydrives toothed belt 18 at any given time.

FIG. 6 shows an embodiment similar to that of FIG. 5. In this case,however, pinions 17 mesh with a cylindrical crown gear 20. Duringrotation of cylindrical crown gear 20, therefore, transfer arms 16together with their attached thread guide eyes 15 are moved in thedirection of the two-headed arrow. In the embodiments according to FIGS.5 and 6 also, distance a of transfer elements 5 or of thread guide eyes15 to former axis F is adjusted simultaneously or synchronously and alltransfer elements 5 or thread guide eyes 15 always have the samedistance a to former axis F in any given adjusted functional position.

The embodiment according to FIG. 7 operates with a closed-track camplate 21. To each transfer element 5 designed as a thread guide eye 15there is attached a transfer arm 16, on which there is disposed anengagement element 22, such as an appropriate pin. Engagement element 22engages in an arcuate or curved elongated hole 23. During rotation ofclosed-track cam plate 21, transfer arms 16 are displaced in this way inthe direction of the two-headed arrow and in this way distance a ofthread guide eyes 15 to former axis F is varied simultaneously orsynchronously.

A method for adjustment of distance a in a manner analogous to that ofthe embodiment according to FIG. 7 is indicated very schematically inFIG. 8. In the embodiment according to FIG. 8, distance a of transferelements 5 is varied or adjusted in the manner of an iris aperture.

It remains to be mentioned that former 2 or the mandrel can be removedaxially through ring traverse 3 after the end of the winding process.According to another embodiment, however, former 2 can also be removedradially through corresponding openings in ring traverse 3.

European application 04005981.8, filed on Mar. 12, 2004 is incorporatedherein by reference in its entirety.

Obviously, numerous modifications and variations of the presentinvention are possible in light of the above teachings. It is thereforeto be understood that within the scope of the appended claims, theinvention may be practiced otherwise than as specifically describedherein.

1. An apparatus for winding a plurality of threads or fibers onto aformer, comprising: at least one ring traverse which may at least partlysurround the former, wherein the ring traverse is configured so that atleast one thread can be fed to the former from each of a plurality ofdifferent feed directions, and at least one transfer element adjustablyconnected to ring traverse, wherein at least one transfer element isassociated with each feed direction and is configured to guide at leastone thread onto the former, wherein the distance between one or more ofthe transfer elements and the longitudinal axis of the former isadjustable.
 2. The apparatus according to claim 1, wherein two or moreof the transfer elements are of equal distance to the axis of theformer.
 3. The apparatus according to claim 1, further comprising anadjusting means connecting one or more of the transfer elements and thering traverse, wherein the adjusting means is configured to adjust thedistance between the one or more the transfer elements and the axis ofthe former and the one or more the transfer elements are adjustedtogether.
 4. The apparatus according to claim 3, wherein the adjustingmeans is a closed-track cam plate.
 5. The apparatus according to claim3, wherein the adjusting means is a servo or stepping motor.
 6. Theapparatus according to claim 3, wherein the one or more transferelements configured to adjust together are always disposed with the samedistance to the former axis.
 7. The apparatus according to claim 1,wherein at least one of the transfer elements has a thread guide havingthe shape of an arc or of a ring segment.
 8. The apparatus according toclaim 1, wherein a transfer element is configurable as a thread guideeye.
 9. The apparatus according to claim 1, wherein the distance betweenthe transfer elements and the axis of the former is adjustable with aniris aperture present in the adjusting means.
 10. A method for winding aplurality of fibers onto a former, comprising: feeding at least onethread to the former from each of a plurality of different feeddirections with one or more transfer elements associated with each ofthe feed directions, and adjusting the distance between the transferelements and the axis of the former for at least some of the transferelements.
 11. The method according to claim 10, wherein the distance isadjusted simultaneously or synchronously for at least some of thetransfer elements.